I'm glad this thread is still active and helping others. Still not sure why there are so many problems with this flash. I have an old and well used 580 and it works flawlessly. Mine was actually a board issue and that seemed to have solved the prob...
A month ago I purchased a 600EX RT and since day one got the dreaded low battery indicator. Didnt matter if I used food alk or NiMh'sin it the fash would not power on. Tried all the tricks with button holding, lock then on etc and never really worked...
